"Not only does this result to a lack of choice but ultimately the complete control of our society; those who don't support their agenda are weed."

There are a few grammatical issues in this sentence.

"result to" needs to read "result in..."

after "but," use a comma and similarly after "ultimately."

I am not sure what "this" refers to or who "their" refers to as there is no context provided. Take care to ensure that if this is singular (one thing)- for example, the government or society- then "their" needs to be "its."

The semi-colon has, in fact, been used correctly and continues the thread. The two thoughts are independent clauses and can therefore be punctuated using a semi-colon.

Perhaps at the end of the sentence , the intention was to say "weeded out." The sentence then makes sense:

"Not only does this result in a lack of choice but, ultimately, the complete control of our society; those who don't support their agenda are weeded out."

Im not sure the rest of the sentence is correct but that semi colon is used correctly. A semicolon can be used in two different ways; the first is to start a list with detailed descriptions of the items (e.g this very list); or to split a sentence in half, used as a kind of conjunction where no conjunction fits, like in your example.

I really hope this helped, if you need help with any other grammar message me or ask on this site as I am very willing to contribute long and detailed interesting answers with examples and so-on.